Self-opening die head



June 12, 1951 R. M. STICKLAND 2,556,742

- SELF-OPENING DIE HEAD Filed April 20, 1948 4 Sheets-Shea?l 1 June 12, 1951 R. M. STRICKLAND SELF-OPENING DIE HEAD 4 Sheets-Sheet 2 Filed April 2o, 194e June 12, 1951 R. M. srRlcKLAND SELF-OPENING DIE HEAD 4 Sheets-Sheet 4 Filed April 20, '1948 nl Il Patented `lune 1K2, 1,951

UNITED" STAT QS SELF-OPENIN G DIEHEAD RoycezM. StricklamLN ew Haven, Conn., assigner,

by mesneassignments, togjGreenielm'lap and Die Corporatiorl-.(lieenleld,` Mass., a corporation of Massachusetts Application April-20, 1948;v Serial No. 22,052

6 Claims.

Ther present; invention relates to improvements,`

inaself-:opening'.'dieeheadsi:and: relates more. par.-

ticularly.Y to self-opening'. die-heads which.. are.

suitable, for the cutting..v of;` tapered threads,

though .also available. for the;` cutting. of straightthreads..

One; oi:the. main objects; offthe present 1 invention is teaprovide; a. superior` self-opening. die.-v

Af; further object lof f the present invention is` to provide a superior self-opening die-headirhaving; a; construction Y, and. arrangement of parts whereby it is. substantiallyv freenof cramping` or binding; ofA its.- ,parts under stress.

Still another object. ofi the present. invention.

inte-,provide aseli-openi-ng die-headfof the-.gen-

erallcharacter. referredto which is provided with mplur'alityof thread-cuttingchasers andis capa-v blefof accurately:v cutting .threads .which progressii/ely; decreasey in diameter.v as the .cutting operation progresses, and characterized by. the .surety withewhich eachV andevery. oneofr'its chasers will perform itsrshare` ofthe threadingtask..

Aast-ill further objectoi-Jthe presentinvention isf: tor.. provide a superior#self--openingA diehead capable fof. cutting tapered. .threads in` an accu-Y rate. and `.reliable manner and provided with superior means. whereby: its'. plurality of `threadicutting. chasers may be-progressively-and accuratelymoved vradially with respect tothe .worki being. threaded by. either the work itself, orby.'

external means.

Other objects will be apparentto{those-:skilled in the. artfrom the following, considered-lin conjunction withy theaccompanying drawings;

1n the. accompanying drawings., in which' certain'modesof carryingout the present invention are shown .for A illustrative purposes ;V

Fig; 1 is a .view in frontelevation of oneiorm-Y which a self-openingV die-'head'I embodying. the4 presen-t invention may assume with the chasers shownin position for thefstart of the cuttingfofy ataper thread;

Fig. 2 is a view thereof in sidew elevation; Fig.. 31 is `a central longitudinal sectional view takennnf the line -3t-3 of-'Eig. 1, but on a larger` scale;

LIU

Figi'. 4- isa transverse sectional View taken on the lined-4 of Fig. 3;

Y Fig- 5l isla similar view, but taken on the line- 5-5 of'Fig. 3;

Fig. 6 is a broken longitudinal sectionalview taken on the line --Eil of Fig. 5;

Fig. 7" is a similar View, but taken on the,

line 'l-'l of Fig. 5;

Fi`g. 8V is a broken longitudinal sectional Viewv taken on the line 8---8 of Fig. 5;

Fig. 9 is a perspective View of the control-` plate detached;

Fig, 10 is a similar view of the control-sleeve detached;y

Fig.' 11v is a perspective view of the controlplate,` control-sleeve and actuating-bar shownin the positionswhich they assume at the startof' the' threadecutting operation;

Fig. 12 is a view similar to Fig. 11, but showing' the parts in the positions which they'a'ssume afterthecompletion` of the threading operation andv` after thev movement" of theV thread-'cutting chasers into their retired or clearance positions; Fig. 13 is a central longitudinal sectionalview similar-v to Fig. 3; but* showing the parts in the" positions awh-ich they assume upon the completionofthe-threadecutting"operation and just prior to thernovement of the parts into position to permitltheretirement vof -thethread-cutting chasers;

Figi 14^is-la perspective View similar to Fig. l1, but showing a-slight 'modication of the elementsy in order to secure the-production-ofastraight thread andl Fig.- 151s a viewsimilar to Figs. 11 and-14, lout1 showingia-still further. modificationof the. elements in order to-provide for the production oirtapered threads which progressively increase in diameters as. the threading progresses.

The structure. of- Fz'gs. 1 150,13 inclusive' Theparticular self-opening die-head chosen forilhistration in Figs. 1 tof-13 inclusive forpurMV pesesof-.making.=clear apreferredembodiment of the present invention, is so organizedas tenuti tapering-threads which progressively decrease in diameter-asv the threading operation progressesint contraPdisting-uishment tov an organization Whichprogressively increases the diametersof. the-'threads aslthe. cutting operation progresses.`

Thef4 particular self-opening die-head referred to;.incl-udes 1 a body-member generally designated by; the` reference character 2e which, inturn, includes-at its front a relatively-large-diame.- teredhead-portion-Z and aV rearwardly-eXtend-- operation ,3. ing integral shank 22. The said body-member is formed with an axially-extending cylindrical chamber 23 which opens through the forward face of the head-portion 2| and which extends continuously rearwardly into the shank 22, as'

is especially well shown in Figs. 3 and 13.

The head-portion 2| of the body-member 2Q is formed in its forward face with four (more or less) equidistant radial guide-slots 23, each of which intersects at its inner end of the chamber 23 and at its outer end intersects the outer periphery of the head-portion 2 l.

Mounted with capacity for reciprocation in an axial direction in each of the guide-slots 24, is one of four similar chasers 25 which are retained in place in the said guide-slots by means of four segmental retaining-plates 25 secured to the front i'ace of the head-portion 2|.

Each Chaser 25 is provided with a rearwardlyextending pin 2'|, the inner face of which is engaged by the outer end of a cup-shaped plunger 28. Each cup-shaped plunger 28 is mounted for reciprocating movement in a substantially-radial bore 29 formed in the head-portion 2|. Each plunger 28 is yieldingly urged radially outwardly by means of a helical spring 35 tting within the adjacent hollow plunger and thrusting at its inner end against the bottom wall of the particular bore 29 in which the said spring is mounted, all as is especially well indicated in Figs. 3 and 13.

Each of the chasers 25 before referred to has a sloping cam-surface 3| at its outer end which is adapted to be engaged by one of four similarly sloping cam-surfaces 32 formed upon the inner forward corner o a cup-shaped Chaser-operating sleeve generally designated by the reference character 33.

Within its forward portion, the chaser-operating sleeve 33 is formed with a relatively-largediametered bearing-surface 34 and in its rear portion with a relatively-small-diametered bearing-surface 35. The bearing-surface 312 reciprocates with a smooth sliding t upon the outer periphery of the head-portion 2| of the bodymember 28, while the bearing-surface 35 in the Chaser-operating sleeve is adapted to reciprocate with a smooth sliding fit upon the outer periphery of a control-sleeve generally designated by l the reference character 36, and which will later herein be described in more detail.

The Chaser-operating sleeve 33 is limited to reciprocating movement lengthwise with respect to the body-member 28 by being provided in the interior of its forward portion with a keyway 31 receiving with a sliding fit the outer end of a key 38 seated in the outer periphery of the headportion 2| of the body-member 28, all as is indicated in Fig. 7.

Mounted, in turn, upon the outer peripheries of the Chaser-operating sleeve 33 with capacity for reciprocation in an axial direction with respect thereto, is an actuating-sleeve generally designated by the reference character 39. Within its forward portion, the said actuating-sleeve is formed with a relatively-large-diametered bearing-portion 45 and within its rear portion With a relatively-small-diametered bearing-portion 4| respectively bearing upon the large-diametered outer surface of the forward portion of the Chaser-operating sleeve 33 and the small-diametered rear portion of the outer periphery thereof. Adjacent its rear end, the actuatingsleeve 33 is formed in its outer periphery with an annular groove 42 for purposes as will hereinafter appear.

For the purpose of limiting the movement of the actuating-sleeve 39 to an axial direction with respect to the Chaser-operating sleeve 33 upon which it is mounted, the interior of the rear portion of the said actuating-sleeve is formed with a longitudinal keyway 43 receiving with a free sliding t a key 44 seated in the outer periphery of the adjacent portion of the Chaser-operating sleeve, as is shown in Fig. 7.

Rigidly secured within the Chaser-operating sleeve 33 against the forwardly-facing wall 45 therein, forming the junction between the bearing-surfaces 34 and 35, is a ring-like controlplate generally designated by the reference character 48. The said control-plate is rigidly held in place by a suitable number of screws 41 one of which is shown in Fig. 6.

Thrusting rearwardly against the forward face of the control-plate 45 are two cup-shaped plungers 48-48, both of which appear in transverse section in Fig. 5, from which it will be noted that the said plungers are located diametrically opposite each other. One of the plungers 48 appears in side elevation in Fig. 6 wherein it is shown (both plungers being identical) as mounted for reciprocation in a direction lengthwise of the structure in the head-portion 2| of the bodymember 28. The said plunger receives the rear end of a helical spring 43 which presses at its forward end against the rear face of the adjacent one of the retaining-plates 26, to thereby yieldinglyurge its complemental plunger 48 rearwardly. The rearward thrust exerted by the plungers 48-48 serves to yieldingly rearwardly urge the unit comprising the chaser-operating sleeve 33 and the control-plate 46 secured thereto.

For the purpose of yieldingly urging the control-sleeve 36 rearwardly with respect to the body-member 25 upon which it is mounted, there are provided two plungers 58-58 respectively located diametrically opposite each other, as is indicated in Fig. 5. Each of the said plungers 55 corresponds to the other and each thereof, like the showing of Fig. 8, is mounted for reciprocation in a pocket 5| extending lengthwise in the control-sleeve 33 and opening through the forward face thereof. Each of the said plungers is urged forwardly by a helical spring such as the spring 52 indicated in Fig. 8. The spring-pressed plungers 58 just described, serve to normally yieldingly maintain the rear face of the controlsleeve 36 seated against a ball-bearing assembly 53, as is indicated in Figs. 3, 6, 7, 8 and 13.

The ball-bearing assembly 53 above referred to, rides against the forward face of an iadjusting-sleeve 54 which is threadedly connected to the outer periphery of the shank 22 of the bodymember 28 immediately to the rear of the control-sleeve 36. The turning of the adjustingsleeve 54 serves to change the normal axial position of the control-sleeve 3B as may be required for adjusting the diameters of the threads to be cut by the chasers 25. Mounted in the outer periphery of the adjusting-sleeve 54 is an inwardlyretirable stop-member 55 which normally serves to stop the rearward movement of the chaseroperating sleeve 33 when the same is released to the action of the spring-pressed plungers 48, in a manner as will hereinafter appear.

Mounted within the chamber 23 in the bodymember 20, is an actuating-slide `56 which is adapted to reciprocate in the said chamber, in

assegnazse aman-nenas. will. hereinafter appear. The saids actuating-slide. is.Y formed with a.. centrallongitudinal lbo1e,5l andv withl a diametrical bore 58, bothofwhichbores intersectpeach other, as is Clearly shownin Figs. 3 vi and 13.

Threaded into, the longitudinalbore 51 in the.. actuating-slide 56, is an adjmstablel abutment: member 59 which is adapted to have its forward end engagedwvith the vouter endV of a piece of work.: b eing?threa ded, in a manner as willhereafter appear. The. periphery; of .the rear portion of, the., abutment-:nemica er .59 is provided-with; as, pluralityy of longitudinal de tent-,groovesv 6,6. whichare Yadapted to be sequentially, engaged by ag-,lock-screw 6-1 andfby -a detent-ball yS2. The said .lockscrew 6i is threaded into one end ofra rodlilielactuatingA-bar 63 Which extends through the-.,diametricalbore:58 in theactuatingsleeve 5.6; The detentball 5 9... above referred.. to, is. mountedin. ,therend oftieactuatingsbar 63, Oprnositeiheloehfscrew i 8 i and isyieldinely, pressed intoeengagement withonerof. the. detentrgrOoVeS Safor.: the;` ahutmentmember. 59.E by means-,Off a helicalsprine.; eli-,i asis shown especially Wellin.

The; actnatingrslide.: 5 6 .'and;V the partes carried thereby,-v includinge the v elements Ez and. 63,: ai'B-, yieldingly urged forwardlyibymeans Df. ailielical spring.55; as. isrshownvinlEigs., 3 and- 13. The

centralsportion' ofthe. actuating-bar 63 is..pro-.

vided with.:.aediametrical. passage-63a forithe re.- ception-of .thefabutment-.member 59.

li'rorn1 the foregoingrandhy.. reference to the drawings,- it will beobserved .that .the actuating: barfilextends,diametricallyiwith respect to the` actuating-slide-- and projects-from the. respec-v tive opposite sides thereof, as isespecially wellshown in Figs. 3, 4 and 13. The adjustable-abutment-membex; 59.;-,thedetent-grooves 60 of which are engaged `by the locking-screw 5| and detentbalIEiZ, extends diametricallythrouglrthecentral portion ofthe actuating-bare@ atV diametrically-opposite points withlongitudi- 4 nal clearance-slots "S 666"`through both" of *which-V the actuating-bar 83" extends with freedom-for' slidingmovement therein. in a direction length'-l wiseof the body-member 2e.'

The control-sleeve 3Gis in turn, formed' at diametrically-opposite points with two actuatingslots.. 6l-61 through which the actuating-bar 63' extends with freedom for movement lengthwise in the said actuating-slots, The' actuating-slots E-'l just referredtofinstead of extendingfin' oarallelismwith theaxisof vthe body-membert22A are. inclinedin a .helical path, asis especially weil' sliOWn in Figs. 10 11 `and',.12`.

The .learportion of the Chaser-operating siee'z'e 33 isl formed 'at diametricallyfopposite points with clearance-slots B 8-68 'through' which extends the actuating-bar 63.

' The respective opposite ends ofthe actuatingbal.. G3i above described iprojectinto clearancegrooves llill-69 formed Within1the interior of thev rear portionl ofthe actuatingsleeve 39. The said clearancegrooves extendin a direction paralleling.A theaxis of the saldi actuating-sleeve.V

Leading, radially from the outer surface of the actuating-sleeve 39 .respectively into intersecting relationship withA respect to the clearance-grooves. 6914629; are... threaded` passages llll-respectivelytthreadedlyreceiving.plugs 1I-7 I, which lattery seryejo., excludedirt, chips and other foreign,

matterfiem the interior.of.thedie-heacl;y One of; the saidf plugs-.l1 may?. berremoved toiI affordi' accessito thelock-screwt l The. ring-likecontrol-plate M ;isprovided with four; (more. or less) inwardly-exteriding.4 -contrcle lingers 12 equidistantly spacedromzeachothers ina circumferential.direction and each havingits rear face. sloped to provide. a Vrearwardly.-facine.- The :control-surfaces. 'I @sub1-,.-

controlsurface 7.3; stantially.: correspondiin.. inclination. to the ine clined. forwardly-facing.; control-surfaces.. h1

formedupon the control-sleeve 3lslightlyto.. the.

rear.; of the extreme-f forward end ofthe said. con: trol-sleevev Circumferentially adjacent the A,forward termi- L nus of each of its control-surfaces 'Mf the. control-sleeve Stils-formed withaone of four-similar.

forwardly-opening; clearanceenotches; 151 which Theoperationvv of the structure offFiys.- 1 t0 13 inclusivey Letis be'assumed for purposes ofy description,

* thatth'ef-self-opening die-head-has its parts-in the positions in whichtheyare shown in Figs;V

l to ll-inclusive,I in which the chasers-25 are inl position to sta-rt thethreading` of fa work-piece;y

Shortly after theteeth' at the inner ends'of the' chasers 25 engage withL and startto thread fthe periphery of the said work-piece, the forward'- endof` the abutment-member 59 within-the1-die head structurev will engagewith the-vendiof theY saidwork-piece- Under. present conditions', either thedie-head structure5 the work-piece, o-rboth,

maybemoved in an axial direction-with respectl to the other, andeither the .die-head,v the-work piece,.or. .boththereof :may be. rotated with 'respect-t toeachother. Itis .the more usualpractice-tok rotate the die-headstructure with respect to the work-piece.

After the .forward end of the.abutment-rneniberrA EQengages with thelworkepieceeits forward move.- inent .will thereby behalted relative tothe workpiece.. as. will also thesforwardinovement .ofthe actuatingfslide-EG andthe. actuating-.bar 63. The.; remaining parts. of thev die-head.. structure will. continue to.. move. forwardly relative to; theiworkpiece-against thev tension..,of the springy 65, so;

that; relative movementr will take place in an axial direction between thezactuating-bar 63 and the-surfaces of thehelically-inclined actuatingslcts E37- 61. In effect, the actuating-.bar 63willA move; rearwardly inthe said actuatingslots 61 and this movement will cause the said actuatingsleeve to turn inthe direction indicatedV by.; the

arrowv in Fig.p11.

rihe above described turningmovement of the control-sleeve 36. will turn its inclined4 controlsurfaces M relative tothe similarly-inclined control-surfaces i3 ofthe control-plate i6 andthe resultant camming action will move the said control-plate forwardly relative to the body-member 20. The described forward movement of. the

control-plate 46 will (since the parts 4ev and 33 thereby. progressively. move the latter radially.

inwardly. The described inward movement of the chasers will be progressive and at a rate which is predetermined and in accord with the desired taper of the threads to be produced upon the work-piece indicated in Fig. 3.

At the completion of the desired threading operation, the described turning movement of the control-sleeve 3G will have brought the parts into the relative positions in which they are indicated in Fig. 13. A minute further turning movement of the control-sleeve 36 will bring its clearance-notches 'I5 respectively fully into registry with the control-lingers 13, whereupon the spring-pressed plungers S-AS (Figs. 5 and 6) will snap the control-plate 66, together with the Chaser-operating sleeve 33, rearwardly until the rear end of the said Chaser-operating sleeve strikes the stop-member 55. The relative positions now assumed by the parts 36, 46 and 63 are shown in Fig. 12.

The described rearward movement of the Chaser-operating sleeve 33 will retire its camsurfaces 32-32 rearwardly relative to the camsurfaces Si on the chasers 25, thereby permitting the said chasers to move radially outwardly under the urge of their respective springpressed plungers 23. The described movement of the chasers 25 will clear the thread-cutting teeth thereof from engagement with the work, whereupon the now-threaded work-piece and the die-head may be axially separated.

As above described, the relative rearward movement of the actuating-bar 63 and the consequent turning of the control-sleeve 36 to provide the progressively-reducing taper thread is accomplished by the engagement of the stopmember 59 with the work-piece. The same result could be achieved by any instrumentality such as a yoke (not shown, but well known in the art) riding in the annular groove 42 in the outer periphery of the actuating-sleeve 39. This will be clearly apparent when it is observed by reference to Fig. 3 in parti-cular, that any relative rearward movement of the actuating-sleeve 3S relative to the remainder of the structure would cause the forward wall of its clearancegrooves S9 to force the actuating-bar 63 relatively rearwardly in the same manner as such action was accomplished by the relative rearward movement of the abutment-member 59 and the actuating-slide 55 to which it is attached.

After the chasers 25 have been moved into their completely retired positions, as previously described, following the completion of the threading operation, the said chasers will require resetting to restore them into substantially the 'positions in which they are shown in Fig. 3, in order to start another thread-cutting operation.

To effect the resetting of the die-head, the chaser-operating sleeve 33 may be moved forwardly relative to the body-member 20 and its chasers 25 and this may be accomplished by an external instrumentality riding in the annular groove i2 in the actuating-sleeve 39. Thus, if the actuating-sleeve 3S is moved farwardly relative to the body-member 2.0, it will, `in turn, force the Chaser-operating sleeve 33 forwardly.

As soon, in the forward travel of the chaseroperating sleeve 33 and its attached control-plate t5, as the respective rear faces of the controliingers 12 are brought into registry with the high points of the control-surfaces 'M on the controlve the said control-sleeve will be free to tern in a direction opposite to the direction indicated by the arrow in Fig, 11. This rotary move- 8. ment of the control-sleeve 36 will be under the urge applied by the spring B5 acting through the actuating-bar 63 and the actuating-slots 61.

The parts will now have reassumed the positions in which they are shown in Figs. 1 to l1 inclusive, preparatory to the start of another threading operation.

The structure of Fig. 14

In Fig. 14 is illustrated a slightly modified form of control-plate and control-sleeve respectively similar to the control-plate 46 and the control-sleeve 36 before described, and bearing similar reference characters with respect to their various features, plus the reference character a.

The control-plate 46a illustrated in Fig. 14 has four inwardly-projecting control-fingers 12a, each of which has its rear face providing a control-surface 13a. Instead of being inclined as are the control-surfaces 13, the control-surfaces 13a extend in a plane at a right angle to the central longitudinal axis of the structure.

The structure of Fig. 14 also includes a controlsleeve 36a similar to the control-sleeve 36, save that its control-surfaces 14a, extend in a plane at a right angle to the longitudinal axis of the structure to complement the control-surfaces 13a of the control-plate 46a.

Now, when the control-sleeve 36a is turned with respect to the control-plate 46a, in a manner similar to that described in connection with the structure of Figs. 1 to 13 inclusive, the control-plate 46a and parts connected thereto will not be moved forwardly, so that instead of cutting a thread which progressively decreases in diameter as the threading operation proceeds, a series of threads of uniform diameter will be produced.

The sructure of Fig. 15

In Fig. l5 is illustrated -another slightly modiiied form of control-plate and control-sleeve respectively similar to the control-plate 46 and the control-sleeve 3S before described, and bearing similar reference characters with respect to their various features plus the reference character b.

The control-plate 4Gb illustrated in Fig. 15 is provided with four inwardly-projecting controliingers 12b, each of which has its rear face providing a control-surface 13b. Instead of being inclined in the direction of the control-surfaces 'I3 before referred to, the ycontrol-surfaces '13b slope in an opposite direction.

The structure of Fig. 15 also includes a control-sleeve 36h similar to the control-sleeve 36 save that its control-surfaces 'Mb slope in a direction opposite to the slope of the control-surfaces' 74 before described. The control-surfaces 13a and the control-surfaces 14a substantially coincide in their respective inclinations.

When the control-sleeve 36h is turned with respect to the control-plate 4Gb in a manner similar to that described in connection with the structure of Figs. l to 13 inclusive, the controlplate 4Gb and the parts connected thereto Will move rearwardly so that instead of cutting either a straight thread or a thread which progressively decreases in diameter as the threading operation proceeds, there will be cut a series of threads which progressively increase in diameter. The invention may be carried out in other specific ways than those herein set forth Without departing from the spirit and essential characteristics of the invention, and the present emlibodiments '-are, therefore,l -to= be considered inf-all #respects las illustrative yLandrnot frestictiva f and all-changes coming within `the meaning :and I-equivzilency range lof lthe 4Lappended claims l are Ifclaim:

'1. 4'Ascii-opening die-head having -a=iorward Chaser-carrying Vportion-f and including incomlbinai'fion: -a body-unit comprising a body-mem- Yber, -a -chaser-operat-ing l sleeve carried/by and reciprocating Y in 'a substantially-axial "direction with respect to the said body-member,-'an'dlimiting-*means -interconnecting the saidbody-unitand 'Chaser-operating sleeve vand*l limiting the-relative movement therebetween to aireoiprocating movement in vsubstantially 'an axial direction,I the -said vbody-unit being provided with a'sub'stantiallylongitudinal slot and the said A `chaser=operating sleeve being providedwith a'plurality 'of laterally projecting controlngers; 4al plurality of "chasers 'carried 'by the 'forward :portionof the saidI body- 'member' with capacity for movement toward and away from the longitudinal axis thereof; the said chasers being' operatively connected with' the said 'Chaser-operating sleeve 'for being moved .thereby toward the longitudinal axis of 'the die-head structure on axial movement of said Chaser-operating sleeve in a certaindirection; .a controlsleeve carried'by the said'body-unit for movement axially therewith'but having capacity for oscillating movement ina circumferentialdi- Arection with respect i thereto andprovidedwith a substantially-longitudinal slot inclined with respect to the .slotvof the said body-unit, the .said control-sleeve also having its forward end .formed .into a .plurality of circumferentially- -fspaced cam-surfaces .engageable-by the controlngers of the .said Chaser-*operatingsleeve,-said Aforward end of said control-sleevebeing further provided with a .plurality of.forwardlyopening clearance-notchesadjacentits said cam-surfaces, respectively; andan actuating-member extend- -ing into the respectiveslots of both thefsaidbodyunit andithe` said'control-'sleeveand constructed vand arranged to coactwithther wallsof the two saidyslots to forcethe said control-sleeve'to turn Y in la* circumferential direction'relative to the bodyunit vwhen the' saidactuating-member -is moved inA the. direction substantially lengthwise of the diei-head i structure to thereby Ecause the plurality of'cam-surfacesfof the control-sleeve to slide in a generally-circurnferential `direction and cooperate with the control-fingers of the Chaser-op- Aerating-sleeve in axially moving the vlatter sleeve Y lin=said certain direction, said Chaser-operating sleeve being knormally yieldin'gly urged axially in "the opposite direction'so that the same will, when itscontrol-ngers align with and are urgedinto said clearance-notches in said control-sleeve, `move in the latter direction and thereby permit quick movement of said 'chasers away frornthe longitudinal axis of said body-member.

'2. `A self-opening die-head having aforward phaser-carrying portion andfincludingA inlcomsleeve'to slide ina generaliy-circumferential"divsleeve--beinglprovided` -ly-extendingcontrol-fingers; a pluralityof chas- -=ers carried by the forward portion of the A`said witha pluralityfof inwardbody-member -with capacity for movement Vlrtoward and away from Y thev longitudinal axis thereof, the -sa-id chasers being operatively connected with the said chaser-operatingsleeve'for'being moved thereby toward the longitudinal-axis ofthe die-headstructure on -axial movement of said Chaser-operating `sleeve in V-a certain direction; fa control-sleeve located inter-mediatethe said bodyvmember and thesaidchaser-operatingsleeve and axially-movable -with said body-member but having capacity for -oscillating movement in `acircumferential direction -with respect thereto and provided -with a l substantially-longitudinal l slot inclined with-'respect to the slot ofthe said bodyunit, the saidcontrol-sleeve also having-its forvward end formed into -a plurality of circumfer- `entially-spaced cam-surfaces engageable by -the control-fingers of the said Chaser-operating sleeve, the forward endY ofVK said control-sleevebeingffurther provided with a plurality of forwardranged /to coact with the walls of vthe Ytwo saidfslots yto force the said control-sleeve-rto turn in a circumferential direction relative uto the body-unit when the said actuating-member is moved inthe direction substantiallylengthwwise off the idie-headY structure to *thereby cause the plurality of cam-surfaces of `the "controlrection andrv cooperate with the control-i'ingersof the Chaser-operating sleeve in laxially moving the'latter sleeve'in said certain directionysaid Chaser-'operating vsleeve --being normally yieldingly urged axiallyinthe opposite direction-so 'that the same wilLrwhen' its control-ngers-align chasers away'from'thelongitudinal axis of said body-member.

3. A self-opening die-headhaving a forward chaser-carrying portion and including in combination: a body-member provided with two substantially-longitudinal slots each diametrically opposite the other; a plurality'of chasers carried by the forward portion of the said body-member with capacity for movement toward andaway from the longitudinalraxis thereof; achaser-op- Yerating sleeve surrounding andy reciprocating in a substantially-axial direction with respect to the said body-member .and operatively1 connected with the said chasers to .move thesame inwardly toward .the axis .of the die-headstructure on v.axial movement ofksaid Chaser-operating sleeve in .a certain direction, the said Chaser-,operating l seeve being provided with a plurality of controlfingers and with, two slots diametrically opposite eachother i-n both. registry fand parallelismcwith .the slots in the said body-member; limitingmeans yinterconnecting the said body-member and -chaser-operating sleeve and limiting the `relative movement therebetween'to a reciprocat- 'tween said body-member 'and Chaser-operating ing movement in substantially anaxial direction; c control-sleeve `axially slidably interrltted-I besleeve and axially `movable with said body-member but having `capacity'for-oscillating movement in a` circuinferential direction with respect thereto and being provided with two substantiallylongitudinal slots each diametrically opposite the othei` and in registration respectively with the slots in the said body-member and Chaser-operating sleeve and both inclined with respect to the slots of the said body-member and chaseroperating sleeve, the said control-sleeve also having its forward end formed into a plurality of circumferentially-spaced cam-surfaces engageable by the control-fingers oi the said Chaser-operating sleeve, the forward end of said controlsleeve being further provided with a plurality of forwardly-opening clearance-notches adjacent its said control-surfaces, respectively; and an actuating-rnembei` extending in a substantiallydiametric direction into the respective pairs of slots said body-member and said Chaser-operating and control-sleeves and constructed and arranged to coact with the walls of said pairs of slots to force the said control-sleeve to turn in a circumferential direction relative to the bodymember when the said actuating-member is moved in a direction substantially lengthwise of the die-head structure relative to said bodymember to thereby cause the plurality of camsurfaces of the said control-sleeve to slide in a generally-circumferential direction and cooperate with the control-ingers of the chaser-operating sleeve in axially moving the latter sleeve in said certain direction, said Chaser-operating sleeve being normally yieldingly urged axially in the opposite direction so that the same will, when its control-lingers align with and are urged into said clearance-notches in said control-sleeve, move in the latter direction and thereby permit quick movement oi said chasers away from the longitudinal axis of said body-member.

4. A self-opening die-head having a forward chaser-carrying portion and including in combination: a body-member provided with two sub-f stantially-longitudinal slots each diametrically opposite the other and with an axial chamber intersected by the said slots; a plurality of chasers carried by the forward portion of the said body-member with capacity for movement toward and away from the longitudinal axis thereof; a Chaser-operating sleeve carried by and reciprocating in a substantially-axial direction with respect to the said body-member and peratively connected with the said chasers to move the same inwardly toward the axis of the diehead structure on axial movement of said chaseroperating sleeve in a certain direction, the said Chaser-operating sleeve being provided with a plurality of control-fingers and with two slots diametrically opposite each other in both registry and parallelism with the Slots in the said body-member; a control-sleeve carried by the said body-member interiorly of the said chaseroperating sleeve and being axially movable with said body-member but having capacity for oscillating movement in a circumferential direction with respect thereto and provided with two substantially-longitudinal slots each diametrically opposite the other and in registration respectively with the slots in the said body-member and chaser-operating sleeve and both inclined with respect to the slots of the said body-member and Chaser-operating sleeve, the said control-sleeve having its forward end formed into a plurality of circumferentially-spaced cam-surfaces engageable by the control-ngers, respectively, of the Said Chaser-operating sleeve, said forward end of said control-sleeve being further provided with a plurality of forwardly-opening clearance-notches adjacent its said cam-surfaces,

respectively; an actuating-member extending in a substantially-diametric direction into the respective pairs of slots of the said body-member, the said chaser-operating sleeve and the said control-sleeve and constructed and arranged to coact with the walls of the said pairs of slots to orce the said control-sleeve to turn in a circumierential direction relative to the body-member when the said actuating-member is moved in a direction substantially lengthwise of the die-head structure to thereby cause the plurality of cam-surfaces of the said control-sleeve to slide in a generally-circumferential direction and cooperate with the control-fingers of the chaseroperating sleeve in axially moving the latter sleeve in said certain direction, said Chaser-operating sleeve being normally yieldingly urged axially in the opposite direction so that the same will, when its control-fingers align with and are urged into said clearance-notches in said controlsleeve, move in the latter direction and thereby permit quick movement of said chasers away from the longitudinal axis of said body-member; and a reciprocating actuating-slide movable in the axial chamber in the said body-member and operatively connected to the said actuatingmember to move the same.

5. A self-opening die-head having a forward Chaser-carrying portion and including in combination: a body-member provided with two substantially-longitudinal slots each diametrically opposite the other; a plurality of chasers carried by the forward portion of the said body-member with capacity for movement toward and away from the longitudinal axis thereof; a Chaser-operating sleeve carried by and reciprocating in a substantially-axial direction with respect to the said body-member and operatively connected with the said chasers to move the same inwardly towardthe axis of the die-head structure on axial movement of said chaser-operating sleeve in a certain direction, the said Chaser-operating -sleeve being provided with a plurality of controlfingers and with two slots diametrically opposite each other in both registry and parallelism with the slots in the said body-member; a controlsleeve carried by the said body-member interiorly oi said Chaser-operating sleeve and being axially movable with said body-member but having capacity for oscillating movement in a circumferential direction with respect thereto and provided with two substantially-longitudinal slots each diametrically opposite the other and in registi-ation respectively with the slots in the said body-member and Chaser-operating sleeve and both inclined with respect to the slots of the said body-member and Chaser-operating sleeve, the said control-sleeve having its forward end formed into a plurality of circumferentially-spaced camsurfaces engageable by the control-fingers, respectively, of the said Chaser-operating sleeve, the forward end of said control-sleeve being further provided with a plurality of forwardly-opening clearance-notches adjacent its said controlsurfaces, respectively; an actuating-bar extending in a substantially-diametric direction into the respective pairs of slots of the said bodymember, Chaser-operating sleeve and the said control-sleeve and constructed and arranged to coact with the walls of the said pairs' of slots to 'force the said control-sleeve to turn in a circumferential direction relative to the body-member when the said actuating-bar is moved in a direction substantially lengthwise of the die-head structure to thereby cause the plurality of cam- Surfaces of the said control-sleeve to slide in a 13 generally-circumferential direction and cooperate with the control-lingers of the chaser-operating sleeve in axially moving the latter sleeve in said certain direction, said chaser-operating sleeve being normally yieldingly urged axially in the opposite direction so that the same Will, when its control-fingers align with and are urged into said clearance-notches in said control-sleeve, move in the latter direction and thereby permit quick movement of said chasers away from the longitudinal axis of said body-member; and a reciprocating actuating-sleeve mounted for axial movement upon the exterior of the said chaseroperating sleeve and engaging therewith for moving the latter in said certain direction, said actuating-sleeve covering said actuating-bar and said pairs of slots of said body-member and of said chaser-operating and control-sleeves.

6. A self-opening die-head for conical work, including in combination: an abutment-member extending axially of the die-head and having a work-abutting end and a laterally-extending bar spaced from said end; axially slidably-interfitted chaser, control and operating sleeves, respective- 1y, of which said chaser sleeve is innermost and axially slidable on said abutment-member and said chaser and operating sleeves and abutment-member are connected for independent axial but nonrotational movement relative to each other, and said control-sleeve is connected with said chaser-sleeve for non-axial but free rotational relative movement between them, and has a slot inclined to its axis and receiving said bar for turning said control-sleeve in opposite directions relative to said operating-sleeve on relative axial movement between said abutmentmember and chaser-sleeve in opposite directions;

14 a chaser carried by said chaser-sleeve for movement inwardly toward and outwardly from the axis of the latter; means including cams on said operating and chaser sleeves, respectively, cooperating to move said chaser inwardly and outwardly on axial movement of said operatingsleeve in opposite directions, respectively, relative to said chaser; and means including a camface at one end of said control-sleeve and a laterally-projecting cam-lug on said operatingsleeve cooperating with said cam-face to cause on relative rotation between the latter sleeves in said opposite directions relative axial movement between said operating and control-sleeves in opposite directions, respectively, said operatingsleeve being with its cam-lug normally yieldingly urged against said one end of said controlsleeve and the latter having in said one end and adjacent said cam-face an axially-extending notch into which jumps said cam-lug on clearing said cam-face, thereby permitting axial movement of said operating-sleeve in one of said opposite directions in which to permit quick outward movement of said chaser from operative engagement with the work.

ROYCE M. STRICKLAND.

REFERENCES CITED The following references are of record in the le of this patent:

UNITED STATES PATENTS Number Name Date 2,130,181 Hogg Sept. 13, 1938y 2,271,641 Hogg Feb. 3, 1942 2,471,250 Strickland May 24, 1949 

